Quadrilaterals
A quadrilateral is a two-dimensional shape with four sides and four angles. There are a lot of different kinds of quadrilaterals: familiar ones like squares and rectangles and less familiar ones like parallelograms and trapezoids. Quadrilaterals are classified based on the number of parallel lines, equal sides, and angles. Watch this lecture series and complete the interactive exercises.
Practice
Identify quadrilaterals - Answers
1. The following shapes are quadrilaterals:
2. The following shapes are rectangles:
[Isn't the first one a square?]
Yes, it is!
A rectangle is a quadrilateral with four right angles.
Squares are quadrilaterals. Squares have four right angles.
So, squares are rectangles!
3. The following shapes are squares:
4. The following shapes are rhombuses:
5. The following shapes are quadrilaterals:
6. The following shapes are rectangles:
[Isn't that middle one a square?]
7. The following shapes are squares:
